Brake



Sept. 20, 1,932. Q STONER 1,878,911

` BRAKE Filed July 2e,- 1950 2 sheets-sheer 2 [lll/111111111111.

' While this brake applying mechanism pro- Patented Sept. 270, 1932 eEoEc-E H. sToNEzaorBosToN, MAssACHUsETTs, AssrGfNoE To sToNEEg-AMEs BRAKE COMPANY, ING., oF-BosTort MASSACHUSETTS, A CORPORATION or rfrAssAoiarr-V -SETTS of substantially semi-circular brake shoes con- '110 nected at adjacent ends to a commonpivotal mounting. rlhe shoesare'moved into engagement with the brake drum by rsepara-ting the free ends by a mechanism comprising a shaft A., rotatably mounted in the free endof one shoe and carrying a one-lobed cam adapted to en.-

gage the free end of the other shoe. The cam shaft is arranged to move laterally relative to thev backing plate and'is rotated by suitable means operated. by" the usual bralre pedal.

vides for a smooth, soft and powerful braking action, the construction of some standard vehicles is such that some of the parts interf-1 fere with this brake applying mechanism.

1t is an object of the present invention to provide a brake applying mechanismembodye ing similar principles which is adapted for general application. e y @a A further obj ect of the invention isv the proapplying mechanism.

Before explaining infdetail the present in;

requirements thereof.

The invention will be more clearly understood from the following description in conjunction with the accompanying drawings, in Vwhich:

vision of an improved self-centering brake terms of the several claims hereto appended as considered in viewr of the prior art and the,

BRAKE Application led. July 26, 1930.y Serial No. 470,929. n i

Fig. 1 is a side elevatiompartly in section, of the vehicle brake embodying the invention, the parts being shown in the relative lpositidcns they assumel before the brake isV expande i 'Y f i 1 l Fig. 2 isla top plan view, Apartly in 'secl' tion; l' Y .e f Fig. 3 is a detail perspective view of some of the parts of the Vbrakeoperating mechamsm; i .i l

Fig. 4 is a perspective view of one ofthe members forming part of the bralreoperating mechanism;

Fig. 5 is a top plan view, partlyinfsection,

of a brake embodyin'ga modified form l,of the o invention; 1

Fig. 6 is a side elevation'of a portion of the modiiied brake operating mechanism ;v and Fig. 7 lis a perspective viewof some of the members forming part of the modiedV brake operating mechanism.

One embodiment of tratedinvligsgl to 4 ofthe vaccompanying drawings whichshows abrake comprising a brake shoe composedv offsections 10 land 11 suitably mounted4 upon va fixed backing plate 12 sov as to be moved intoand out of engagement with a brake drum V14 rotatable with the vehicle wheel. The brake shoes 1() and 11may be ofV any usual construction, but,v as illustrated each may comprise'a'substantial non-deformable member 15 and a deformable.

contact memberj16 carrying a suitable fric- A `the brackets20` is provided with an opening ISserVingfaS; a bearing foraneccentrio shaft v21 carrying l an eccentric 22 engaginga circus` lar opening 19in the member 15. Each shaft 21 is providedwith a head24adapted to enfV gageJone ofthe brackets 20. and is locked against'rota'tion by a suitable clamp, such `as a nut 23 engaging the opposite Vbracket the invention is illus@ The members 15and 16 of each brake shoe arev secured together at Vone endbya suitable bracket 25 having a projection 26 provided with a curved end adapted to be received in a groove 27 in the edge of a block V28 mounted upon an anchor pin 29,7Which is adjustably mounted upon the backing plate` 12, as by a nut 31 on the pin 29 engaging the plate 12. A spring is secured at its end to each of the members 15 Withits intermediatelzportion in engagement-With the block .28 so as tortend to move each of the shoes 10 and invvard with respect to the block.

One mechanism `en'ibodying the Ainvemzion for. separating 'the free dends of the y shoeslO and 11 to bring them in engagement with the drum may comprise a cam shaft 35 sup-l `ported solely by one of the brakeshoes: or this purpose, the free end offene oft-hemembers 1,5 ispositioned inagroove 3 8 in a block 37'havin'g abearing 34`or 'ifotatablysupporting the :shaft 35; 4VThe' fblock 37' is secured to the member l''by'bolts 39 which also serve to secure Vacap"40 'to'theblock 37. lThe cap 40 also embraces the free. fend Noit-the other member v-15 and holds itin slidingengagement VWith the block 37. The outer end Vofthe shaft `35 rotatably supportedhin a bearing l41' in. the cap 40.'I A""ca`m 45 iscarried by the `shaft 35 and vis ,positioned thereon betvveengthe block 37Vandthe cap V470 so' as toyengage the free end of the member'l' which iSslida'ble between the `cra-pand block. Theinnerend of the shaft 35i-Lis provided gWith ,Y a square' end 46 (see 'particularly -Fig. adapted to be received in a similarly shaped hole47 in a. disk48., The disk 48 is provided vwith i a slot 49 offsetfrom the center thereof, and

providing bearingV faces l50-'tor a cam 51 ,carriedby ashaft 52 mounted'for rotation Ain a bracket` 53 secured to-th'e backing platefas'by bolts 54. `The shaft 52is connected to the brake pedal of fthe vehicle V(not shown) by the usual mechanism including a lever clamped upon the shaftf52.Y

.l nousA 54'.

In operation the brake shoes 10 and are expanded` againstthedrum- 14 by .depressing the brake pedalv (not engagement With-the drum 14.'.

,inthe-brake embodying the moaidlgfrmf of brake operating mechanism'illustrated in shown) to causerota-4 tion. of the shaft 52 to 'bring the vcam 5l into engagement jwithone of the 'bearing faces $56 on the rotatable vmember for disk "48 1and'turn t'he same. Rotation Yof member 48 causes rotation of the shaft '35j to movegthe'cam 45 into engagement Withith-e kfree end of the member 15 rwhich isnslidably` mounted 'bef' tween'the cap 40. and'the'blockg? Vand thus,Y

i' separate the members l y to `'brigngithemjin.

is provided with a projection of cylindrical shape having a peripheral slot 61 adapted to receive the free end of one of the members annular ring 62 Which serves as a bearing rotatablyv supporting the lmember 48. The' ringi62isprovided With a peripheral opening 63 ofthe same Width as the slot 61 and Which terminates in surfaces 6 4 Vnormally positioned lAslotibb is formedin the-'peripheryof the ring 62 diametrically opposite the opening 63 and is adapted to receive the free end of the otherjmemberl which is secured thereto,

as`by' set screWs6'6l The bottom 56 of the fslotlserveszasacam. 4 Y I y Thecam-shafft 52 lisrotated by operation of the brake pedal causing the `cam .51 `to engage with yone of the faces 50 to rotate the member 48.causingthe,bottom-56 of the `slot 61ste actas `a cam lto separate the shoes l5 and bring them, into engagement .with the drum. 4It vWill be noted-that .the opening 63 in `thering62 is, ,in effect, a -continuation of theslotl inthe projection .60 and.` that `the the ring 62. f

fIcclaim: 7 l

Q Al. .In anv internal expanding lorake,`a `brake drum, a pair ofbrake shoes, a .disk carriedfby one of said shoes :and having a peripheral slotto receive theother shoe, a member .rotatably `carried Aby said diskV and having a vslot in oneface, :means .actuated bysaid member andoperable in the slot-in said disk to engage saidY other shoe, andA means adapted .to slidably-engage .the slot inL said .member to rotate Y 'said member.

` .2. In an .internal expanding brake, a `brake drum, a pair ofbrake shoes, a disk carriedby v one of said shoesand havinga peripheral slot Figs.V 5 to 7 in clusive,"the shaft 52" carrying. i'

thecam 51 is rotatably mounted in a bracket n,

plate `l2f,as by 53" secured tothe backing .A rotatable member. or disk48 is Vrotatably positioned against the backing plate 1'2iand its' inner face is provided Withl K aslot-49 offset Afrom the centerthereof Vand Providing bearing surfaces 50 cam 15111;, outer face Yoit' the member 43? toreceive the a 15. The Vprojection 60 is surrounded by an c member v15 inserted 'in .the opening 63 and Y Vslot k61..etfectively locks the `member 48 `to 

